Filter.



PATENTED OCT. 10, 1905.

C. L. PARMELEE.

FILTER.

APPLICATION FILED D120. 1. 1904.

wwcnfot WW @MW "UNITED STATES PATENT OFFICE.

FILTER.

Specification of Letters Patent.

Patented Oct. 10, 1905.

Application filed December 1,1904. Serial No.

To fl/ZZ whom. it nm/ concern:

Be it known that I, CHARLES LESTERPARME- LEE, a citizen of the United States, residing at Orange, in the county of Essex and State of New Jersey,have invented certain new and useful Improvements in Filters, of which the following is a specification.

My invention relates to filters, and more particularly to that class thereof wherein cleansing apparatus is employed, and is designed to simplify and cheapen the construction thereof and at the same time to obviate the defects existent in previous systems.

As is well known in the art, it becomes necessary after the filter has been in use for some time and the filtering-bed thereof has become clogged with impurities to cleanse it thoroughly, and this is accomplished by forcing a liquid through the pipes located at the bottom of the tank, from which it passes upwardly through the filtering-bed and finally flows over the containing-wall, when it is removed in any convenient manner. forms of filters it is desirable to use air or some other gas as an agitating or purifying medium in connection with the process of washing or independently thereof. It is obvious that this gas must likewise be distributed throughout the tank beneath the filtering medium and in such manner that it will completely permeate the entire mass. If the air or gas were forced through the pipe which conducts the washing liquid into the filter, as formerly constructed, the greater portion thereof would escape through the orifices which are nearest the source of supply, because of the large cross-sectional area of the holes. To avoid this objection, several systems have been introduced comprising separate pipes for the gas and the liquid, the former being provided with vents considerably smaller in size than the ordinary holes in order that the gas might be evenly distributed beneath the filter-bed. In the systems referred to the air or gas pipes were located in various relations to the water-pipes, sometimes alternating in position with them and in other cases located entirely within them. In order to do away with the necessity for separate gas-conductors, a system was designed, as illustrated in the United States Letters Patent to \Villiamson, No. 653,160, July In some 3, 1900. In one of the forms illustrated in the said patent the air is forced through the water-conduits, which latter are constructed and formed so that the water remaining therein constitutes an internal seal or trap and shuts off the water holes or apertures and compels the air to escape by means of vents of much smaller size, thus forcing the air to be evenly distributed throughout the entire system and permitting it to escape under all parts of the filter-bed and insuring its complete agitation and scouring.

It is my present intention to providea system whereby the water seal or trap is produced externally to the piping instead of within it, thus achieving the same results in a simpler and cheaper manner.

My invention consists in the construction and combination of parts, as illustrated in the drawings, described in the specification, and finally pointed out in the claims.

Referring to the drawings, Figure l is a vertical section of a filter system, taken on a line parallel with the piping. Fig. 2 is a sectional view taken at right angles to the piping. Fig. 3 is a detail sectional view of one of the pipes on an enlarged scale and showing the arrangement of the perforations, the latter being of exaggerated size; and Fig. 4 is a view similar to Fig. 3, illustrating a slightlymodified form of pipe.

The arrangement and construction of the filter proper may be of any suitable or wellknown type and form no part of my present invention. For the purposes of illustration 1 have shown a plurality of filters provided with. side walls A and containing filtering material B, supported upon strata C and D of coarser material in the manner well understood in the art. \Vhen the filter is in actual operation, the water to be purified is introduced into the main channel G, from which it passes into branch channels G Gr. and then it overflows the walls A onto the filterbed. It then passes through the filtering medium into the drain-pipes E E, by which it is conducted to the conduits F F and from thence to the main conduit F. \Vhen it is desired to cleanse the filter, the operation is reversed and washing-water or other liquid is admitted to the main conduit F and branch conduits F F and drain-pipes E E to the bottom of the filter-bed, through which it rises and finally overflows the walls A A to the conduits G G.

All of the parts already described may be of any suitable or desired construction, with the exception of the drain-pipes E E, to which my invention particularly relates.

The drain-pipes E E, as best shown in Fig. 3, are provided with two sets of perforations, one set, M M, located near the top of the drainpipes and the other, N N, located near the bottom thereof. The lower perforations N N are of considerably larger cross-sectional area than the upper perforations M M, which latter are purposely reduced in size so as to afford considerable resistance to the passage of air or gas therethrough, and thus to cause its distribution throughout the entire system. The drain-pipes E E, as previously stated, are arranged beneath the filter-bed and, as shown in the drawings, are maintained in proper position by the braces O O and communicate directly with the conduits F F. During the ordinary operation of the filter the water passes from the filter-bed into the drain-pipes E E, through the perforations M M, as well as the perforations N N, although chiefly through the latter, because of their larger size.

When air or other gas is to be forced through the filter-bed for the purpose of its agitation and cleansing, it is admitted first to the conduit F and from thence to the conduits F F. The air or gas naturally occupies the upper parts of these conduits and forces any water therein into the drain-pipes E E until it can itself pass into the drain-pipes. As the upper vents M M therein are of small cross-sectional area, the water in the drain-pipes E E is forced through the larger apertures N N at the bottom and is continually displaced from the pipes E E until all the upper openings M M are in use and the air or gas escapes through them all. When the air or gas passes through the openings M M, it breaks the water layer at the bottom of the tank and passes upward through the filter-bed, thus insuring the thorough agitation and aeration of the entire bed. However, the water below the vents M M remains practically undisturbed and by its pressure supports a body of water within the drain-pipe E, as indicated in Fig. 2, and as these external and internal bodies of water are connected by the openings'N N it will be seen that the latter are effectively sealed against the passage of air or gas therethrough and that this condition will continue so long as air or gas is introduced into the conduit F. As previously indicated, an external trap or seal is thus secured for the water-holes, which depends on the liquid outside of the drain-pipes.

In Fig. 8 the perforations M M and N N are shown as formed in the rounded corners of the drain-pipe E. In Fig. 4 I have illustrated a slight modification wherein the holes M M and N N are shown in theside walls of the square pipe E. Their function is, however, the same as that already described, and, generally speaking, the precise form or location of the perforations constitutes no part of the present invention. Similarly, the exact shape, location, and construction of the pipes may be varied at will, and, generally speaking, I desire also to include within the terms pipe and piping all varieties of underdrains to which the present invention may be applied.

It will be seen that I have provided a simple and efficient form of apparatus for securing the desired results and that I am thus enabled to dispense with the more or less complicated and expensive devices-previously employed for the same purpose. The drainpipe E may be formed of metal, tile, or any other desired material.

Having thus described my invention, its construction, and mode of operation,what1 claim, and desire to secure by Letters Patent of the United States, is a follows:

1. In a filter, a system of piping provided with a plurality of rows of perforations for the gas and a plurality of rows of perforations for the liquid during the operation of gascleansing, the former being of smaller crosssectional area, and the latter being arranged to be sealed externallyby the liquid containedwithin the filter.

2. In a filter, a system of piping, provided with a plurality of rows of perforations for the gas and a plurality of rows of perforations for the liquid during the operation of gascleansing, the former being located at the top of the piping, and the latter being located in the lower portion in position to be sealed ex; teirnally by the liquid contained within the ii ter.

3. In a filter, a system of piping provided with a plurality of rows of perforations for the gas and a plurality of rows of perforations for the liquid during the operation of gascleansing, the former being of smaller crosssectional area and being located at the top of the piping, and the latter being located in the lower portion in position to be sealed externally by the liquid contained within the filter.

4. In a filter, a system of piping rectangular in cross-section and provided with perforations in the sides thereof respectively for the gas and liquid during the operation of gascleansing, the former being of smaller crosssectional area, and the latter being arranged to be sealed externally by the liquid contained within the filter.

5. In a filter, a system of piping rectangular in cross-section and provided with perfo- IIO rations in the sides thereof respectively for the gas and liquicl during the operation of gascleansing, the former being located at the upper portion of the piping, and the latter being located in the lower portion in position to be sealed externally by the liquid contained within the filter.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

CHARLES LESTER PARMELEE.

In presence of M. WV. CLEP'HANE, R. F. ROGERS. 

